Nasa delays final Endeavour launch for THIRD time as engineers work to fix shuttle's heating glitch

Nasa has delayed the final launch of space shuttle Endeavour for the third time since its failed take-off attempt last month.

Engineers are still trying to fix an electronics problem which scuttled the spacecraft just moments before it was due to blast off from the Kennedy Space Center, Florida.

But an unmanned rocket faced no such glitches when it blasted off from the neighbouring Cape Canaveral Air Force Station on Saturday morning.

Another delay: Endeavour's launch has been rescheduled for May 16 . It is seen here on Pad 39A moments after its original launch was halted in April

The Defense Department's unmanned Atlas 5 rocket had been delayed from Friday by bad weather, but successfully launched at 2.10am to carry the first satellite of a new missile-warning system into orbit.

Share this article

Share

Meanwhile Endeavour will now launch no earlier than May 16 as it makes its 25th
and final mission, to deliver the $2 billion Alpha Magnetic
Spectrometer particle detector to
the International Space Station.

Nasa had to stop the countdown on April 29 because of a problem with a heating system on one of the ship's hydraulic power generators.

The heaters keep
fuel from freezing in the power lines, preventing it from rupturing in the cold
vacuum of space.

False start: Commander Mark Kelly and two other crew members pictured as they made their way to the launch pad before April 29's aborted take-off

Long job: Endeavour sits on the launch pad as technicians take a break from repairing a glitch in an electrical box which grounded the shuttle

At first Nasa was hopeful that the problem would have an easy solution and had
rescheduled Endeavour's launch for the following Monday.

However further troubleshooting
indicated the glitch was more complicated than officials initially thought, and the take-off date was moved to May 8.

The problem was traced to a microwave-sized box of switches in the rear engine compartment which routes electricity to the heaters.

It was replaced on Wednesday, and since then technicians have been running a series of tests on the switches, which will continue over the weekend.

Disappointment: President Barack Obama and his wife Michelle pose with Endeavour crew members just after the launch was aborted on April 29

Engineers have had
to replace external wiring too, in case the problem originated from outside
the device.

Nasa spokesman Kyle Herring said: "There is still some uncertainty because we have to get past all the work.

'We'll
regroup on Monday and see how far they've gotten over the weekend, but
the (May 16 launch date) looks pretty good right now.'

Endeavour's six astronauts have returned to Johnson Space Center in Houston
for additional training before they return for the next launch attempt.

Recovery: Gabrielle Giffords is determined to watch Endeavour's launch, and was seen out for dinner with husband Mark Kelly last weekend

Crew family members who had travelled to Florida to watch the launch
also returned to Houston, including stricken U.S. Representative
Gabrielle Giffords, the wife of Endeavour commander Mark Kelly.

Ms Giffords, an Arizona Democrat, is recovering from a near-fatal shooting
in January at a public meeting in Tucson, Arizona.

She was shot in the head at close range in an attack which left six
people dead and 13 wounded. Ms Giffords has made a miraculous recovery
and is determined to watch the take-off.

GABRIELLE GIFFORDS: A REMARKABLE RECOVERY

Arizona congresswoman Gabrielle Giffords has made an astonishing recovery since she was shot in the head at close range during a public meeting outside in Tucson on January 8.

She was well enough to fly to Florida last month for the aborted Endeavour launch, and was seen slowly making her way up the plane steps unaided.

Ms Giffords made only her second public appearance last weekend, when she went out for dinner with her husband, Mark Kelly, and another couple.

Accompanied by security personnel, she was taken by wheelchair to a private room at Grotto Ristorante in the city's Galleria area on Sunday.

They were joined by Tilman Fertitta, president and chief executive of Landry's Restaurants, and his wife Paige.

Student Jared Loughner has pleaded not guilty to 49 federal charges in connection with the shooting.

Hopes of her returning for the rescheduled launch were raised further
last weekend when she was seen having dinner with Mr Kelly at a
restaurant in Houston, only her second public appearance since the
shooting.

The Endeavour mission is the next-to-last for the 30-year-old shuttle
program, which is ending after sister ship Atlantis completes its final
voyage this summer.

Endeavour was the replacement ship for Challenger, which was lost in a
fatal 1986 launch accident. It is the youngest of Nasa's three surviving
spaceships and the second to be retired.

Discovery, the fleet leader, returned from its final space mission in
March, and Atlantis is due to end the shuttle program with a launch on
June 28.

Meanwhile the U.S. Air Force began a series of unmanned missions with its Atlas 5 launch today.

The rocket was carrying the $1.3 billion Space-Based
Infrared Systems (SBIRS) Geo-1 spacecraft, the first satellite of four scheduled to launch over the next five years.

They will provide the U.S. military with early notice of
missile launches and other reconnaissance services.

The $17.6 billion project will eventually replace the military's Defense Support Program satellites, which have been operating since 1970.

Roger Teague, head of the U.S. Air Force's Infrared Space
Systems Directorate, said: 'Geo-1 will bring the dawn of a new era in persistent overhead
surveillance.

'These systems are so much more sensitive. We can see much more, much earlier, much sooner (and) many dimmer targets.'